Hydraulic propulsion of ships, boats, and other floating structures



June 4, 1940. w, DIAMANb 2,203,010

HYDRAULIC PROPULSION 0F SHIPS, BOATS AND OTHER FLOATING STRUCTURES FiledMarch 6, 1939 4 Sheets-Sheet J.

" 1940- w. DIAMAND 2,203,010

HYDRAULIC PROPULSION OF SHIPS, BOATS, AND OTHER FLOATING STRUCTURESFiled March 6, 1939 -4 Sheets-Sheet z June 4, 1940. w. DIAMAND 2,203,010

HYDRAULIC PROPULSION 0F SHIPS, BOATS, AND OTHER FLOATING STRUCTURESFiled March 6, 1939 {sheets-Sheet 3 w. DIAMAND 2,203,010

HYDRAULIC PROPULSION OF SHIPS, BOATS, AND OTHER FLOATING STRUCTURES June4, 1940.

Filed March 6, 1.959 4 Sheets-Sheet 4 Patented June 4, 1940 UNITEDSTATES PATENT OFFICE HYDRAULIC PROPULSION'OF SHIPS, BOATS, AND OTHERFLOATING STRUCTURES Wiiold Diamand, 'Lwow, Poland Application In 14Claims.

This invention relates to an improved hydraulic propelling mechanism forships, boats and the like floating structures (hereinafter referred tocollectively as boats) of the well known type acting through a waterpiston in which means the working delivery pipe is filled from an inletconduitor pipe with water, which after the closing of the delivery pipefrom the inlet pipe is accel-' the speed of the water in the intakepipe. An-

other object is to provide means for cushioning the shock of theexpansion of working gas in the delivery pipe.

The new propelling device according to the invention may be mountedwithin the hull of the boat with the water-inlet member and the outletof the expansion tubes communicating with the outside water. It may alsobe constructed as a separate self-contained structure mounted within aspecial hull or casing and attached to the boat in any suitable way andat any suitable point.

According to this invention hydraulic propulsion means of the said typeinclude an intake pipe associated with a plurality of delivery pipes anda rotary device which connects the intake pipe successively with thedelivery pipes which are circularly arranged in relation thereto.

By this meansa stream of nearly constant speed relatively to the body ofthe boat can be maintained in the inlet pipe.

Preferably shock absorbing mechanism is provided which takes the excessof pressure caused by the expansion of the working gas.

According to a further/feature of the invention the delivery pipes maybe provided over that portion of their length within which gas expansiontakes place with a. narrowed or restricted cross-section in order thatthe speed of the water flowing through may exceed that of the boatitself. This special arrangement has been found of particular usefulnessin boats of small speeds, it permits higher initial pressures and theuse of a more compact propulsion mechanism.

For shallow-going watercraft the hydraulic gear according to theinvention is preferably so constructed that the depth of immersion ofthe outlet ends of the expansion tubes may be varied March 6, 1939,Serial No. 259,968 Great Britain May 5, 1937 during the travel of theboat. For this purpose the rear portion of the propelling mechanism maybe turnable through a small angle about a horizontal axis. In thesecases too the expanded gas preferably'leaves the delivery tubes through5 their walls rather than at their ends. For this purpose small slitsmay be made in the wallsof the delivery pipe the slits being cut on thetop side of the delivery pipe at an angle to the axis thereof so that onthe interior of the pipe the 10 front edge of the slit, thus nearer theinflow end of the pipe, presents an acute angle with a sharp edge to thewater and gas flowing therethrough, but on the exterior of the pipe thefront edge of the slit presents an obtuse angle to the water 15 flowingthereover, the slit therefore running backward from the inside to theoutside of the pipe. Other similar slits may be arranged the oppositeway round to take in water to replace the loss of volume due to theescaping gas. Experiment 20 has shown, that by means of such slits thegas, escaping through the slits, can be separated in suitablecircumstances from the water, and the decrease in volume may be made upin that part of the tube by supplying fresh water through the otherslits which may be similarly constructed as the above described.

The inflow end of the common inlet pipe is preferably arranged about themiddle of the boat's length.

A still further feature of the invention consists 30 in the arrangementof a rotating valve disc con trolling the water inlet to the deliverypipes by controlling the mouth thereof, cutting the same off the commonwater inlet tube during a period of time within which the compressed gasenters the delivery pipes (where it may be ignited), and subsequentlyexpands, and providing a controlled valve mechanism introducing thecompressed gas into the delivery pipes in the required quantities 40 orportions and being preferably so constructed as to permit the use ofcomminuted fuel, for example, coal dust.

According to a further feature of the invention the boat propellingmechanism is provided at the inlet ends of the delivery pipes, with aquickly closing valve disc or plate, so arranged and actuated as topermit an accelerated closure of the delivery pipes and thus preventdisturbances at the inlet side thereof. This additional controlingelement is preferably mounted upon the aforementioned rotating valvedisc, so as to be positively actuated while rotating therewith.

The delivery pipes are preferably so curved,

that the water passing through them will be subjected to a centrifugalaction in a direction opposite to gravity. This helps the formation of awater surface substantially normal to the direction of the water flowand adapted to act as a piston surface.

All the amounts of compressed gas used are produced outsidc theoperating cylinders and admitted to them while already being in theircompressed condition.

The compressed air needed for combustion inside the delivery pipes orany kind of gas under pressure after being compressed in a separatecompresser, may be heated up to the required temperature in asuperheater of any suitable kind by the heat quantities delivered, e. g.by exhaust gases of the internal combustion engine driving theaforementioned compresser.

'In the particular case of a. propelling mechanism using comminutedsolid fuel, for example, pulverised coal, the compressed air during theadmission thereof into the delivery pipe passes over coal powder,carrying with it into the delivery pipe a quantity sufiicient for onecom- ,bustive operation, the air speed being so adjusted that the coalpowder will be distributed in and uniformly mixed with the compressedair admitted.

The air-fuel mixture under pressure introduced into the delivery pipeproduces within the admission end thereof a water-free space so that thefuel carried along cannot pass into the water body so as to escapeignition. This action of keeping the fuel separate from the water bodycan be improved, according to a further feature of the invention by theopening stroke of the mixture admitting valve being effected in twosuccessive steps or stages. During the first stage the compressed air iskept off the fuel, so that compressed air alone will enter the operatingcylinder. Only when the second stage is reached will the compressed airpass over the powdered fuel so as to mix the same uniformly with the airand to inject it into the cylinder.

According to a still further feature of the invention the improvedhydraulic propelling mechanism is associated with a pneumatic shock absorbing contrivance, by which the irregularities of the propelling forcearising from the variable pressure in the delivery pipe, can be smoothedout. This contrivance substantially consists of a part of the mechanismon which the gas pressure acts immediately to cause it to make in thedirection of the boats motion a slight reciprocating lengthwisemovement. So for example a pneumatic compensating contrivance may beemployed in which the pressure of the expanding or burning gas actingupon such moveable part of the mechanism causes the displacement of apiston which reciprocates against the reaction of the gas compressed ina compressed gas reservoir. This reciprocation induces a periodicalchange of the volume of the compressed gas reservoir. If therefore thevolume of the reservoir is sufiicient any small amount of theirregularity or variability of the boat's propulsive force may be dampedout.

Further features of the invention will be apparent from the subsequentdescription of the accompanying drawings illustrating more or lessdiagrammatically some embodiments of the invention.

In the said drawings:

Figure 1 is a partial longitudinal section.

Figure 2 is a cross section.

Figure 3 is a side view.

Figure 4 is a. section through Figure 3.

Figure 5 is a section of a hydraulic device controlling the gas inletvalve.

Figure 6 is a cross section of the valve in the fully closed position.

Figure 7 is a cross section of the valve in the fully opened position.

Figure 8 is a longitudinal section of a pneumatic shock absorbingcontrivance.

Figure 9 is a section through a delivery pipe showing slits for thedischarge of the expanding gases therethrough.

In the drawings the reference numeral l designates a main water inletpipe through which a co-axial pipe 3 extends and to which is joined anouter tubular extension 2. The outside water in which the boat floatsthus may pass continuously through the annular space formed by themembers I, 2 and 3 respectively. At its rearward end the water inletspace is closed by a disc 4 having an aperture 5 of the shape of a Iring sector and being continuously rotated in the direction of the arrow(Fig. 2). On a circle concentric with the aperture 5 the centres of thesubstantially circular ends of a plurality of, for example four,delivery pipes 6 are arranged upon which disc 4 rotates with a liquidtight contact. The disc 4 is actuated by a central shaft 1 and asuitable actuating mechanism, for instance a worm gear as indicated at 8is indicated in the drawings. The mouths of the pipes 6 are providedwith lateral extensions, as indicated at 9' in the drawings. The pipes 6are preferably of greater diameter at their outlet or discharge endsthan at their inlet ends and extend lengthwise substantially in theshape of a prolonged fiattened S so that the water passing through thefirst bend which is bent downward will be sub- I ject to a centrifugalaction counteracting gravitation, which tends to ensure that the watersurface in the pipes 6 will be substantially normal to the directionofthe water flow, and thus causes a diminuation of the-surface of the gasspace.

The disc 4 is located within a casing 10, the edge ll of the discaperture 5 controlling the beginning of the water inflow from the mainwater inlet l into the delivery pipes. In order to accelerate theclosure of the water inflow the disc 4 is provided adjacent the otherend of aperture 5 with a control flap l3 having a small inertia momentand being pivoted on a pin l4. This flap is adapted to shut the mouthsor inlet ends of the delivery pipes off from the water inlet, as soon asthe edge I 2 of the lattice l5 has advanced beyond the mouths of thedelivery pipes and passed thereover. It is constructed of thin sheetmetal and is supported against the gas pressure by a fixed sheet metallattice l5. That lattice will be preferably situated in such a position,as to oppose to the water stream, flowing therethrough after thereopening or before,

the closure of the flap, only a smallest possible resistance. The metalsheets forming the lattice .may be thus placed approximately in thestream and pipe 3 being filled with a suitable heat insulating material.

Disc 4 is intermediate its'control edges-provided with the inletaperture for an expansible gas, for example a combustible gas mixture.This inlet aperture communicates withthe backward end of the pipe 25 bya conduit not iilustrated in the drawings and is controlled by a valvemechanism 26.

The cycle of operations is as follows: The disc 4 rotates in thedirection of the arrow shown in Figure 2. Water flows into the pipes 6from the time that the edge ll of the disc aperture 3 has passed overthem until the edge I! of the lattice II has also passed over them. Atthis moment the control flap l3 closes the opening of the pipe 8 by arapid movement, thus avoiding cavitation in the pipe which might occurif the closure was a slow one. The valve body II has meanwhile come infront of the mouth of the delivery pipe. The compressed .gas is injectedinto the mouth of the pipe is ignited and expands giving the workingstroke. The mouth meanwhile of the pipe iull of oil. In the casing ll ofthe disc us mounted a concentric inner cam 21 on which a roller 23 rollsand controls the valve inquestion.

The cam lug 23 will move the roller when it passes over it and therebyalso move the piston 31 downward, so that it expels the oil into thesleeve 34 and causes a movement of the plunger 33 and so opens the valveagainst the force of a spring 38 and of the gas pressure acting on thepiston 33, which holds the roller against cam 21. The power output ofthe propelling mechanism will be controlled by effecting a changeof theopening interval of the valve 23. A contrivance may be thus providedwhich brings this about by the opening of an admission valve 40 (or ofan overflow valve) of the above oil pump. The circular cam, whichcontrols that admission valve may i be constructed so that it may bemoved rotationally through a small angle in order to change the openingmoment of the admission valve or over-flow valve of the oil pump, and soto accelerate or retard the moment at which the valve 26 closes, and soto control the power output.

' The disc 4 is further provided with suitable gas igniting means notshown which at the proper moment of time cause the ignition-of thecombustible mixture admitted to pipes 6.- y

In the drawings a preferred embodiment of compressed air andfueladmission valve, adapted to be incorporated with an internal combustionengine according to the invention, is shown diagrammatically. Thereference numeral 4i designates the inlet opening controlled by thevalve 42, the conical valve seat 43, amember upon which the valve ismounted and having a front face 44 adapted to contact with the outerfaceof an expansion tube or cylinder, which is not illustrated in thedrawings. 45 located at a small distance behind the front 44 if thevalve is closed, is attached to a discharge piston 46 by means of avalve stem comprising a section 41 having a relatively large diameterand a section 43 of smaller diameter. Theadmission of the compressed airtakes place throughapertures 43 which are in a continuous or in 9.

The valve cone controlled communication with a suitable source ofcompressed air. The coal dust or powder is admitted through a passage 50leading into a hollow sleeve 5|. The outer end of sleeve 5| is closed bystem portion 41, if the valve is in its closed position. When the valveopens stempressed air carrying fuel with it and intimately.

intermixing itself therewith. The quantity. of fuel carried alongdepends upon the duration of the valve opening. If the same varies thequantitles of compressed air and of fuel admitted to the expansion tubesare simultaneously varied.

The mechanical means for operating valve stem 41, 43 are not illustratedin the drawing and may be of any suitable kind. I

As shown from the drawing the valve cone 45 has to travel a distance a,before the feed'of fuel from sleeve II can begin, the valve thus at eachvalve operation admits at first compressed air only and after the travela has been effected compressed air and fuel are admitted.

The pulverised coal can be fed to the mixture valve for example in thefollowing manner. side the hollow shaft 1 might be mounted ceritraliy aworm, by which the coal powder can be drawn into a space formed on theright side of the disc 4. Afterwards the coal powder will be taken alongwith a small quantity of compressed air. This could be effected forexample by an injector device supplied with compressed air from a smallbranch of the inlet air pipe located at a small distance from the placeof the mixture inlet valve to which the coal powder is to be supplied.The volume of the pipe leading from the injector into the mixture valvewill be sufficiently great i to provide the necessary mixture for onecombustive operation the proportions of fuel to air being. such thatcombustion will be initiated in this -chamber and will take place fullywhen it reaches the *delivery pipe. The pulverised coal will reach themixture valve with its temperature still raised, that is almost in a.glowing state, and

will there become mixed with the quantity of heated and compressedairneeded for; the combustion process. The complete mixture present willbe, after closing the valve, quickly ignited inside the delivery pipe bysuitable means of any kind; for, example, an electric spark.

In a different embodiment of the ignition mechlength-wise movement withrespect. to the main water inlet member I. For permitting this move-.ment a further anti-leakage packing is provided at 3| between pipe 3 andmember, 'l, the whole structure composed of disc 4, casing l0, tubes 6,shaft 1 and tubes 2 and 3 being mounted for reciprocating .movement upona suitable pneumatlc, shock-absorbing mechanism 32, which absorbs theshocks caused by the propelling mechanism and keeps them oil the body ofthe boat.

Figure 8 shows one of the various possible embodiments of a doubleacting shock absorbing contrivan'ce, adapted for compensation of theshocks caused by the boat propelling mechanism which will act whetherthe movement of the boat is forward or backward. A fixed cylinderconsists of two parts 52 and 53. Inside them a piston 54 rigid on ashaft 65 is secured to the propelling mechanism. 0n the other end of theshaft (which is well machined) a second piston 55 is freely mounted andreciprocates inside the cylinder 53. A ring 56 secured by means of ascrew nut 51 forms a limitation of the stroke. A second limitationconsists of the shoulder 58 which is fixed to the body of the cylinder53.

When the boat is travelling forward, and pressure exists in the cylinder53 and the reservoir, piston 55 because of its greater area will bemoved to the right, and will take with it piston 54 and the shaft 65 onwhich piston 54 is fixedly mounted and this movement will continue untilpiston 55 rests against the shoulder 58. In this position the hole 60will be closed by sleeve 6|. The driving apparatus will then be in aposition free to perform a further slight backward reciprocatingmovement and is balanced against such movement by the balance ofpressure in the system formed by the cylinder and reservoir on the onehand and the thrust between the driving apparatus and the boat on theother.

With an increase of such thrust the driving mechanism will move to theright. This will take with it shaft and piston 54, which movement willbe resisted by the gas in the cylinder and reservoir.

If the average force of the thrust increases the shaft 65 and piston 54will be displaced sufficiently to the right for hole 60 to pass beyondthe point 62. Gas will then flow into the system from the expansionchambers in the delivery pipes through hollow shaft 65 and orifice 66until the thrust is again balanced, thereby creating a new datumpressure in the cylinder and reservoir.

If, on the other hand, the thrust diminishes to any extent, piston 54will move to the left till holes 64 which are normally to the right ofholes 63 come in register with the holes 63. This will allow pressure toescape until the balance is restored again creating a new datumpressure.

If the boat is moving backward and the thrust between the boat and thedriving mechanism is in the opposite direction, the position of theparts will be with the piston 55 floating in the cylinder 53, hole 60covered by the sleeve 6|. The ring 56 prevents movement of piston 55 tothe right. If the thrust of the mechanism increases there will be a pullto the left on the shaft 65 and on the two pistons 54 and 55. As piston55 is of a greater effective .area than piston 54, this will be resistedby the gas in the cylinder. The thrust of the mechanism is accordinglybalanced against the pressure in the cylinder and reservoir.

Should, however, the average thrust of the system increase the partswill move into the position shown in the drawing, hole 60 will beuncoveredby sleeve 6|, gas will again flow into the cylinder from thehollow interior of shaft 65 and hole 60 returning the parts to theiroriginal position, restoring the balance and giving a new datumpressure.

If the average thrust falls piston 55 will be displaced further to theright by the pressure in the cylinder taking with it piston 54, theholes 64 will come into register with the holes 63 and allow pressure toescape until the correct datum pressure is again reached and the balancerestored. I

In Figure 9 the delivery pipe is shown at 66 the ducing a gas into thedelivery pipes and causing I it to expand therein and a rotary deviceoperating between the inner ends of the inlet and delivery pipes-whichconnects the intake pipe with the delivery pipes and successively closesoff the delivery pipes from the intake pipes during the moment of theexpansion of the gas in each delivery pipe.

2. Means for hydraulic propulsion of boats which include an inlet pipehaving the outer end open to the water outside the boat and an inner endinside the boat, a plurality of delivery pipes having outer ends open tothe water outside the boat and inner ends inside the boat circularlyarranged with reference to the inner end of the inlet pipe, means forintroducing a gas into the delivery pipes and causing it to expandtherein the delivery pipes and close off from the inlet 1 pipe in turnthe ends of thedelivery pipes during the expansion of the gas therein.

3. Means for hydraulic propulsion .of boats which include an inlet pipehaving .the outer end open to the water outside the boat and an innerend inside the boat, a plurality of delivery pipes having outer endsopen to the water outside the boat and inner ends inside the boatcircularly arranged with reference to the inner end of the inlet pipe,means for introducing a gas into the delivery pipes and causing it toexpand therein and a rotary device operating between the inner ends of.the inlet and delivery pipes and having an aperture of the shape of aring sector adapted tocome into register with the inner ends of thedelivery pipes as the device rotates so that water will flow from theinlet pipe into the delivery pipes through such aperture and having aportion beyond such ring sector which is also adapted to come intoregister with the inner ends of the delivery pipes and close off fromthe inlet pipe in turn the ends of the delivery pipes during theexpansion of the gas therein, said closing portion of the rotary devicehaving a flap valve which is caused to be swung across the inner end ofthe delivery pipe with which it comes'into register so as rapidly toclose oil. the same from the inlet pipe and a metal lattice whichsupports the flap valve against the pressure of expanding gas in thedelivery pipe.

4. Means for hydraulic propulsion of boats of the inlet pipe, means forintroducing a gas into the delivery pipes and causing it to expandtherein and a rotary device operating between the inner ends of theinlet and delivery pipes and having an aperture of the shape of a ringsector adapted to come into register with the inner ends of the deliverypipes as the device rotates so that water will flow from the inlet pipeinto the delivery pipes through such aperture and having a portionbeyond such ring sector which is also adapted to come into register withthe inner ends of the delivery pipes and close oil from the inlet pipein turn the ends of the delivery pipes during theexpansion of the gastherein, said closing portion of the rotary device having a flap valvewhich is caused to be swung across the inner end of the delivery pipewith which it comes into register so as rapidly to close off the samefrom the inlet pipe and a metal lattice which supports the flap valveagainst the pressure of expanding gas in the delivery pipe, the saidrotary device also containing an intake valve through which the gas issupplied in turn to the delivery pipes, which valve is also brought intoregister with the inner ends of the delivery pipes as the rotary devicerotates.

5. Means for hydraulic propulsion of boats through water which includean inlet pipe having the outer end open to the water outside the boatand an inner end inside the boat, a plurality of delivery pipes havingouter ends open to the water outside the boat and inner ends inside theboat circularly arranged with reference to the inner end of the inletpipe, means for introducing a gas into the delivery pipes and causing itto expand therein and a rotary device operating between the inner endsof the inlet and delivery pipes which connects the intake pipe with thedelivery pipes and successively closes off the delivery pipes from theintake pipes during the moment of the expansion of the gas in eachdelivery pipe, the delivery pipes being curved so as to produce acentrifugal action opposed to gravity on the water in that part of thepipe in which the expansion of the gas takes place.

6. Means for hydraulic propulsion of boats which include an inlet pipehaving the outer end open to the water outside the boat and an inner endinside the boat, a plurality of delivery pipes having outer ends open tothe water outside the boat and inner ends inside the boat circularlyarranged with reference to the inner end of the inlet pipe, means forintroducing a gas into the delivery pipes and causing it to expandtherein and a rotary device operating between the inner ends of theinlet and delivery pipes and having an aperture of the shape of a ringsector adapted to come into register with the inner ends of the deliverypipes as the device rotates so that water will flow from the inlet pipeinto the delivery pipes through such aperture and having a portionbeyond such ring sector which is also adapted to come into register withthe inner ends of the delivery pipes and close off from the inlet pipein turn the ends of the delivery pipes during the expansion of the gastherein, said closing portion of the rotary device having a flap valvewhich is caused to be swung across the inner end of the delivery pipewith which it comes into register so as rapidly to close off the samefrom the inlet pipe and a metal lattice which supports the flap valveagainst the pressure of expanding gas in the delivery pipe, the saidrotary device also containing an intake valve through which the gas issupplied in turn to the delivery pipes, which valve is also brought intoregister with the inner ends of the delivery pipes as the rotary devicerotates, the expanded gases flowing out with the water from the ends ofthe delivery pipes.

7. Means for hydraulic propulsion of boats which include an inlet pipehaving the outer end open to the water outside the boat and an inner endinside the boat, a plurality of delivery pipes having outer ends open tothe water outside the boat and inner ends inside the boat circularlyarranged with reference to the inner end of the inlet pipe, means forintroducing a gas into the delivery pipes and causing it to expandtherein and a rotary device operating between the inner ends of theinlet and delivery pipes and having an aperture of the shape of a ringsector adapted to come into register with the inner ends of the deliverypipes as the device rotates so that water will flow from the inlet pipeinto the delivery pipes through such aperture and having a portionbeyond such ring sector which is also adapted to come into register withthe inner ends of the delivery pipes and close off from the inlet pipein turn the ends of the delivery pipes during the expansion of the gastherein, said closing portion of the rotary device having a flap valvewhich is caused to be swung across the inner end of the delivery pipewith which it comes into register so as rapidly to close oif the samefrom the inlet pipe and a metal lattice which supports the flap valveagainst the pressure of expanding gas in the delivery pipe, the saidrotary device also containing an intake valve through which the gas issupplied in turn to the delivery pipes, which valve is also brought intoregister with the inner ends of the delivery pipes as the rotary devicerotates, the delivery pipes having slits on their upper surfaces servingas constantly open orifices for the expanded gases, the slit beingshaped so that the angle in the inner wall of the pipe is on the inflowside acute and on the outflow side obtuse.

8. Means for hydraulic propulsion of boats through water which includean inlet pipe having the outer end open to the water outside the boatand an inner end inside the boat, a plurality of delivery pipes havingouter ends open to the water outside the boat and inner ends inside theboat circularly arranged with reference to the inner end of the inletpipe, means for introducing a gas into the delivery pipes and causing itto expand therein and a rotary device operating between the inner endsof the inlet and delivery pipes which connects the intake pipe with thedelivery pipes and successively closes off the delivery pipes from theintake pipes during the moment oithe expansion of the gas in eachdelivery pipe, the delivery pipes being mounted so that they are free toperform small reciprocating movements with reference to the boat whichare resisted by a gas filled cylinder with a piston adapted toreciprocate therein and a gas reservoir in communication with thecylinder.

9. Means for hydraulic propulsion of boats through water which includean inlet pipe having the outer end open to the Water outside the boatand an inner end inside the boat, a plurality of delivery pipes havingouter ends open to the water outside the boat and inner ends inside theboat circularly arranged with reference to the inner end of the inletpipe, means for introducing a gas into the delivery pipes and causing itto expand therein and a rotary device operating between the inner endsof the inlet and delivery pipes which connects the intake pipe with thedelivery pipes and successively closes oi! the delivery pipes from theintake pipes during the moment of the expansion of the gas in eachdelivery pipe, the delivery pipes being mounted so that they are free toperform small reciprocating movements with reference to the boat whichare resisted by a damping device consisting of a cylinder, a piston insuch cylinder connected to the delivery pipes, a reservoir incommunication with such cylinder and valve means connecting the cylinderwith the gases in the delivery pipes so that small movements of thedelivery pipes following increase of pressure in the delivery pipescause displacement of the piston which is resisted 'by the gas in thecylinder and greater movements cause the valve to be opened and furthergas to be delivered to the cylinder so as to increase the resistance todisplacement of the delivery pipes.

10. Means for hydraulic propulsion of boats as claimed in claim 9 thedamping device also including another piston of greater area than thesaid firstly mentioned piston which causes movement to be resisted alsoin the opposite direction to that in which it is resisted bydisplacement of first mentioned piston, and for the valve means whichare opened to increase the gas pressure on larger displacement.

11. Means for hydraulic propulsion of boats which include an inlet pipehaving the outer end open to the water outside the boat and an inner endinside the boat, a plurality of delivery pipes having outer ends open tothe water outside the boat and inner ends inside the boat circularlyarranged with reference to the inner end of the inlet pipe, means forintroducing a gas into the delivery pipes and causing it to expandtherein and a rotary device operating between the inner ends of theinlet and delivery pipes and having an aperture of the shape of a ringsector adapted to come into register with the inner ends of the deliverypipes as the device rotates so that water will flow from the inlet pipeinto the delivery pipes through such aperture and having a portionbeyond such ring sector which is also adapted to come into register withthe inner ends of the delivery pipes and close off from the inlet pipein turn the ends of the delivery pipes during the expansion of the gastherein, said closing portion of the rotary device having a flap valvewhich is caused to be swung across the inner end of the delivery pipewith which it comes into register so as rapidly to close off the samefrom the inlet pipe and a metal lattice which supports the flap valveagainst the pressure of expanding gas in the delivery pipe, the saidrotary device also containing an intake valve through which the gas issupplied in turn to the delivery pipes, which valve is also brought intoregister with the inner ends of the delivery pipes as the rotary devicerotates, with an oil pump, hydraulic means communicating the pump withthe valve to cause the operation of the valve, a cam which operates apump an overflow valve and a cam operating the overflow valve andcontrolling means by which the setting of the cams may be varied so asto control the amount of gas admitted by the valve.

12. Means for hydraulic propulsion of boats which include an inlet pipehaving the outer end open to the water outside the boat and an inner endinside the boat, a plurality of delivery pipes having outer ends open tothe water outside the boat and inner ends inside the boat circularlyarranged with reference to the inner end of the inlet pipe, means forintroducing a gas into the delivery pipes and causing it to expandtherein and a rotary device bperating between the inner ends of theinlet and delivery pipes and having an aperture of the shape of a ringsector adapted to come into register with the inner ends of the deliverypipes as the device rotates so that water will flow from the inlet pipeinto the delivery pipes through such aperture and having a portionbeyond such ring sector which is also adapted to come into register withthe inner ends of the delivery pipes and close off the inlet pipe inturn the ends of the delivery pipes during the expansion of the gastherein, said closing portion of the rotary device having a flap valvewhich is caused to be swung across the inner end of the delivery pipewith which it comes into register so as rapidly to close oil the samefrom the inlet pipe and a metal lattice which supports the flap valveagainst the pressure of expanding gas in the delivery pipe, the saidrotary device also containing an intake valve through which the gas issupplied in turn to the delivery pipes, which valve is also brought intoregister with the inner ends of the delivery pipes as the rotary deviceend inside the boat, a plurality of delivery pipes having outer endsopen to the water outside the boat and inner ends inside the boatcircularly arranged with reference to the inner end of the inlet pipe,means for introducing a gas into the delivery pipes and causing it toexpand therein and a rotary device operating between the inner ends ofthe inlet and delivery pipes and having an aperture of the shape of aring sector 7 adapted to come into register with the inner ends of thedelivery pipes as the device rotates so that water will flow from theinlet pipe into the delivery pipes through such aperture and having aportion beyond such ring sector which is also adapted to come intoregister with the inner ends of the delivery pipes and close off fromthe inlet pipe in turn the ends of the delivery pipes during theexpansion of the gas therein, said closing portion of the rotary devicehaving a flap valve which is caused to be swung across the inner end ofthe delivery pipe with which it comes into register so as rapidly toclose off the same from the inlet pipe and a metal lattice whichsupports the flap valve against the pressure of expanding gas in thedelivery pipe, the said rotary device also containing an intake valvethrough which the gas is supplied in turn to the delivery pipes, whichvalve is also brought into register with the inner ends of the deliverypipes as the rotary device rotates, a supply of air to said valve, meansfor putting said air under pressure, a supply of comminuted fuel to saidvalve delivering said fuel into the air stream so that it passes fromsaid valve into the delivery pipes mixed with air.

14. Means for hydraulic propulsion of boats which include an inlet pipehaving the outer end open to the water outside the boat and an inner endinside the boat, a plurality of delivery pipes having outer ends open tothe water outside the boat and inner ends inside the boat circularlyarranged with reference to the inner end of the inlet pipe, means forintroducing a gas into the delivery pipes and causing it to expandtherein and a rotary device operating between the inner ends of theinlet and delivery pipes and having an aperture of the shape of a ringsector adapted ;0 come into register with the inner ends of the:lelivery pipes as the device rotates so that water will flow from theinlet pipe into the delivery pipes through such aperture and having aportion beyond such ring sector which is also adapted to come intoregister with the inner ends of the delivery pipes and close off fromthe inlet pipe in turn the ends of the delivery pipes during theexpansion of the gas therein, said closing portion of the rotary devicehaving a flap valve which is causedto be swung across the inner end ofthe delivery pipe with which it comes into register so as rapidly toclose oflf the same from the inlet pipe and a metal lattice whichsupports the flap valve against the pressure of expanding gasin thedelivery pipe, the said rotary device also containing an intake valvethrough which the gas is supplied in turn to the delivery pipes, whichvalve is also brought into register with the inner ends of the deliverypipes as the rctary device rotates, said supply of fuel being soarranged that on opening the valve air will pass at first into thedelivery pipe and thereafter air mixed with fuel.

WITOLD DIAMAND.

